Lapping or grinding machine



.gam 3, 1933. Q H, NORTON l,893,00

LAPEING OR GRINDING MACHINE Filed March 14, 1928 3 Sheets-Sheet 1 50H1' WI* l l l Jan. 3, '1933. C, H.- NORTQN A 1,893,100

LAPPING 0R GRINDING MACHINE Filed March 14, 1928 5 Sheets-5h66?, 2

I0 wnesses :rmlentm jan. 3, 1933. c. H. NORTON LPPING 0R GRINDING MACHINE Filed March 14, 1928 3 Sheets-Sheet wltnesses m .0441. ,J4/Mw Patented Jan. 3, 1933 UNITED STATES PATENT OFFICE CHARLES H. NORTON, OF PLAINVILLE, CONNECTICUT, ASSIGNOR TO NORTON COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS LAPPING OR GRINDING MACHINE Application led March 14, 1928. Serial No. 261,472.

My invention relates to lapping or grinding machines, and particularly to a machine in which a large number of substantially duplicate pieces of work are treated at the same time.

One type of machine employed for lapping round bodies of work comprises a lower stationary lap, an upper rotatable abrasive wheel or lapping member and a rotary cage therebe' ytween adapted to hold a plurality of pieces of work in operative contact with the lapping members. Suah a machine is particularly useful for lapping duplicate pieces of work that are cylindrical in shape or have parallel flat ends. As heretofore constructed and used, such machines have necessitated separating the upper lapping element from the lower lap in order to permit manual replacenient of the pieces of work carried in the cage. This has linvolved a considerable waste of time.

The primary object of my invention is to provide a lapping or a grinding machine of the above described type in which the parts are so constructed and arranged that the work may be loaded in and removed from the cage easily and expeditiously.

With this and other objects in view as will be 'apparent to one skilled in the art, my inventionvresides in the combination of parts set forth in the specification and covered by the claims appended hereto.

f Referring to the drawings 'in which like numerals indicate like parts:

Fig- 1 is a vertical front elevation partly in section of a simplified form of a lapping machine embodying my invention, the cage being in the work loading position and having parts broken away to more clearly show.j the construction Fig. 2 is a vertical elevation of the machine with the cage in the grinding position;

Fig. 3 is a plan view of the machine showing the cage in the loading position;

Fig. 4 is a diagrammatic view of the lap and the work cage showing their relative p0- sitions during grinding;

Fig. 5 is a perspective view partly broken away showing the work feeding and removing mechanism feature of my invention contemplates the provision of mechanism which makes it ,easy4 to load the cage and to inspect the work without material waste of time. For this purpose, I provide manually controllable means which permits the operator to unload the cage after the lapping operation has gone on for a desired length of time, and thereafter by a further manually controlled device he may load the cage for a new lapping operation without removing the cage from the machine. The unloading may be accomplished by mechanism which releases the pieces of work from the cage, as through a closure a retaining part of the machine; and the pieces may be loaded into the cage from an overheadV magazine arranged to feed the pieces, when desired, into the work carrying portion of the cage.

Various constructions may be utilized for this purpose, but in the embodiment illustrated, the cage is mounted for movement laterally so as to expose its work carrying portion outside of the lapping zone. This may be accomplished by mounting both the cage and the lower lap on a slide, so that they may move out from under the upper lap sufficiently -to permit loading the cage.

The embodiment of my invention shown in the drawings comprises a lapping machine for cylindrical work comprising a. suitably shaped base 10 having an annular lapping member 11 rotatably mounted in a sleeve 12 on the arm 13 of the upright portion 14 of the base. A plurality of pieces of round work 15 are adapted to be rotatably held in suitably shaped slots in a cage 16 which is rotatably supported above a lap 18 alongwhich thework i slide on suitable flat and V`ways 23 and 24 respectively on themachine base, as clearly illustrated in Fig. 2. The under side of the slide has a rack 25 meshing with a ear 26 which is driven through a shaft 27, an a'suitsition.7

-Fig. 7, t

able hand wheel 28 is provided to move the slide into and out of an operative lapping position. I

The cage 16 may be suitably rotatedto cause the work to'travel around the faces of the laps, and for this purpose the cage is preferably provided with a ownwardly proecting hub 30 which is secured on the post 31.

he latter is rotatably mounted in the table 22 and the supportin member 20, as illustrated in Fig. 1, the ub 30 bearing on the table 20 and serving to hold the sha t in po- In order' that the ca e may be rotated in all positions of the sli e, I may utilize the construction illustrated in Figs.4 1 and 7, in

accordance with which a main driving pulley on the shaft 36 serves to transmit rotative power to two beveled gears 37 and 38 on the shafts 36 and 31 re ectively. The gear 37v is slidabliyl1 keyed to t e shaft 36, as shown in e key 39 riding in\the elongated groove 40 ofthe shaft 36. The shaft 36 is suitably su ported in bearings on the bracket 42 suspendJed from, the under side of the slide 22. 'Y' The cage 16 `may be suitably formed to hold a plurality of work ieces. In the resent ease, as illustrated iagrammatical y in Fig. 4,"it has slots or openings 45 therein` which are arranged to carry pieces of work with their axes each at an angle to a radial line, so as to accentuate the slidin motion between the work pieces and the laps and so increase the lapping action. It will also be observed that the lap 18 and the path of the work in the .cage 16 are eccentric to the grinding wheel or lapping member 11` s o 'that the pieces of work will traverse laterally across the entire width of thelapping member 11 and so uniformly utilize all of the surface thereof.

The lapping member 11 may be made of suitable material, as for example it may be an abrasive wheel made, for example, of ceramic bonded crystalline abrasive grains, or

itfmay be made of cast iron, in which case thelapping material may consist of a loose abraslve powder and a suitable lubricant,

suchA as oil, which is fed to the work during i the-lapping operation. The lower lap 18 has been illustrated as made of iron, but it will be understood that various suitable materials may be employed for the purpose.

The lapplng member 11 issuitably suspended on a head 50- mounted on the lower .end of the spindle 51 which is rotatably and vertically movable in the sleeve 52 carried in the supporting head 12. The sleeve'may be keyed to the head to prevent its rotation, and it may be raised and lowered by means of the screw threaded hand wheel 54 mounted .on the threads 55 on the sleeve 52. By rotating the hand wheel 54, which has a bearing surface on the upper end of the head 12, the spindle 51 may be raised or lowered to adjust the osition of the upper lap relative tothe wor The upper lapping member4 1l is rotated by means of the pulley 58 fixed to the upper end of the spindle 51 and which is -in turn rotated by `the driving belt 59' coming from a suitable sourcevof power. If the belt is removed, the upper la ping member will remain stationary, an -the lapping .operation will be caused by the rotating cage alone.

It will be apparent that during the lapping or grinding operation, the hand wheel 54 may be moved u wardly to the point of letting the upper ap rest freely on the work and descend under the influence of gravity as the work is reduced in diameter.` It is also feasible to have the head 50 mounted on a universal joint permitting the head to adjust itself freely to fit the various pieces of work throughout the extent `of the cage. It

will be understood that the constructional features of the ldriving head may be suitabl modified in accordance with the type of wor to be lapped o r ground as-.is well understood by one skilled in the art.

' An important feature of this invention involves provision for loading the Work car-l rying cage quickly and easily,'and if-this is to be done automatically I may employ a magazine which willfeed the work pieces one Aby one into the openings of the cage as the i ance with which the magazine carrier comprises spaced walls 60 and61 suitably supported on a'bracket 62 projecting from the 1 machine base. The pieces of work, which are illustrated as cylindrical bodies, may be suitably heldin this magazine as by means of a lever 64 having an inwardly-projecting arm v engaging the lower` piece of work in the maga which is located at one side of the magazine zine. The ar'm is held in position beneath the work by means of a spring 65 tending to push outwardly on the upper portion of the lever, as shown in Fig. 6.

The closure is shown particularly in Fig. 5, and comprises an opening 7 0 in the lap 18,

when the slide had been moved outwardly into the inoperative position. The opening 70 is adapted to be closed by a door 72 having a plane top surface which in the closed position forms a continuation of the lap surface, so that the work will roll over this door without affecting the lapping operation.

In order that this trap door 72 may be operated to permit work to fall through the opening as the cage 16 is revolved, it is supported by means of a rod 75 slidably passing upwardly through the slide 22 and the support 20 and pivotally attached to the door. A lever 76 pivotally connected at a central point by the link 77 to the slide 22 makes it feasible to slide thel rod 75 up and down and thereby close and open the door. The opening 7 0 in the lap is enlarged beneath the surface of the lap 18, as clearly shown in Fig. 1,v

to provide two inwardly projecting shoulders against which the'langed portion 78 of the trap door will engage when pushed upwardly, thereby correctly locating the door when closed. The trap door is pivoted to the rod 75 so that when the rod is drawn to the lowtion shown in dotted lines in Fig. 1 in a recess in the opening in the support 20 whereby the work may fall through the opening onto the sliding shelf 80 and so escape from the machine.

The operation of this device will be apparent from the above disclosure. To load the machine the slide 22 is moved outwardly and the latch 64 at the bottom of the magazine is moved so that as the cage 16 revolves, pieces of work will roll successively into the various openings in the cage until it is filled. Then the slide is moved inwardly by means of the hand wheel 28 until the pieces of work are properly located beneath the upper lapping element 11. Then the hand wheel 54 is ation has been accomplished. Then the lappingmember 11 is raised slightly to release the work and the slide 22 is moved outwardly. Thereafter thev trap door 72 is opened by means of the operating lever 76 and the pieces of work are permitted to fall out of the slot of the cage 16 as the cage continues to revolve.

It will'be understood that the term lapping as used in the claims and specification is to be interpreted broadly as covering a grinding operation, since a lapping machine embodying the principles of my invention may be used either to polish or lap the work or to remove a considerable amount of stock as determined by the nature of the lapping elements and the method and time involved in carrying on the operation. Also it is to be understood that the cage or either or both of the laps may be given a compound movement instead of a simple rotary motion, as herein described, as will be understood by one skilled in the art, to accomplish the lapping or grinding operation. 4

Having thus described my invention, what which are relatively movable to lap a plurality of work pieces simultaneously, a slide supporting the lower lap and cage, and means for moving the slide to remove a. portion of the cage from beneath the upper lap and permit` ready loading of the same.

2. A lapping machine comprising a base, opposed laps and a work carrying cage therebetween which are relatively movable to lap a plurality of work pieces simultaneously, a slide carrying the lower lap and the cage, means to move the slide, a driving shaft on the base, a driven shaft on the slide, and connections between the shafts permitting rotation of the driven shaft for various positions of the slide. y Y

3. A lapping machine comprising opposed laps and a work carrying cage therebetween which are relatively movable to lap a plurality of work pieces simultaneously, means to move the cage laterally to a non-lapping position and expose its work carrying portion outside of the lapping zone and means associated therewith for automatically filling the cage with work pieces.

ing a magazine for work pieces arranged to4 ill the cage when in such inoperative position.

5. A lapping machine comprising two opposed laps, a work carrying cage therebetween which has openings for a plurality of work pieces, means to revolve one of said members to lap a multiplicity of work pieces at the same time, manually controlled mechanism to remove the work pieces from the cage when desired, and means for automatically-loading the cage.

6. A lapping machine comprising two opposed laps, a work cage there etween having provisions for carrying a plurality of work pieces, means to move one of said members to i 4 lap the work, means to move the cage laterally from its operative lapping position andmeans for unloading and loading the cage in such inoperative'position. I 7. Alapping machine comprising two laps i having continuous faces in which opposed circular lines in their operative f faces ,lie in arallel planes, a rotatable work cage theretween having provisions for carrying a plu n frality of work pieces in spaced relation adja- Y cent to .its peri hery, means'for rotating the cage and one o the laps so as to lap'all of the pieces simultaneously to the same size, and manually controlled means to load the cage n aterdthe .lapping `operation has been `comete l p 8.` A lapping machine comprising two opposed lappmg elements and a rotatable work carrier therebetween which are relatively rou tatable to lap the work, said carrier being arranged to rotate andl hold several pieces of the work between the laps during an indefinite rotative period so as to lap a set of pieces to duplicate sizes,v and means acting prior to the n lapping operation for filling the carrier with the piecesfof work without removing it from the machine.

9. A lapping machine comprising two opposed laps, a work carrier therebetween arranged torotate and hold aplurality of work pieces in lapping contact with both laps for an indefinite 'rotative period, and means for automatically loading the carrier without removing it from the machine.

'-35 10. A lapping machine comprising two 9py posed laps having opposed annular lapping faces, a carrier for a plurality of work pieces mounted eccentrically relative to one of said laps and arranged to hold all of the work pieces in. lappin contact therewith while it rotates throng an'indefinite period,` and inean's for loading the'carrier'afterthe comually controllable means to lreload the work cage without removing it from the machine.

13. A lapping machine comprising two opposed relatively rotatable laps and a. rotatable work cage therebetween which has taneously lap all of the work pieces withinv the cage for an indefinite period of time and means to automatically. discharge the work pieces successively from the rotating cage whenever desired.

14./A lapping 4 machine comprising. tw'o opposed relatively rotatable laps anda rotata le work cage therebetween which has openings therein to receive a plurality of work pieces, means to positively rotate one of the laps, Lmeans to positively and continuously rotate the work cage and simultaneously lap all ofthe work pieces therein to the same size for an indefinite period of time and manually controlled-,mechanism to remove all of the work pieces from the cage during the rotation ofthecage. w E

, Signed atl Plainville, Connecticut, this th day of March 1928.

A, l CHARLES H. NORTON.

pletion of the operation of lapping said work v ieces. v p 11., A lapping machine comprisingv two opposed laps and a rotatable work carrying 4 cage therebetween which are relatively movab e to lap a plurality of work pieces, a support for the cage movable laterally to locate the cage `in a non-lapping and loading posi'.-l tion, a drive shaft, fixed bearings therefor, and connections from said shaft lto rotate the cage continuously and give a lapping motion thereto when in an operative position ,be-

tween the laps. l

12. A lapping machine comprising two lapping elements havngopposed faces lying in arallel planes aand a` rotatable work cage inter therebetween, means to cause a 'C5 relatlve rotation between said members, said cage being arranged to hold a plurality of work pieces in lapping engagement with the opposed laps for an indefinite period of' cage rotation,1means for moving the 'cage laterally e5 so as to expose work pieces therein and'man- 

